Hyperpycnal flows control the persistence and flushing of hypoxic high-conductivity bottom water in a High Arctic lake
In the deepest portions of many lakes, zones of high-conductivity bottom water (HCBW) depleted in dissolved oxygen (DO) are present. HCBW and DO are important for determining benthic diversity and abundance, nutrients, and contaminant cycling and understanding the long-term evolution of lakes. We in...
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2018
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fttriple:oai:gotriple.eu:oai:doaj.org/article:61315374aba64c36862e65bce241c866 2023-05-15T14:22:23+02:00 Hyperpycnal flows control the persistence and flushing of hypoxic high-conductivity bottom water in a High Arctic lake Ted Lewis Scott F. Lamoureux Alexandre Normandeau Hilary A. Dugan 2018-12-01 https://doi.org/10.1139/as-2017-0022 https://doaj.org/article/61315374aba64c36862e65bce241c866 en fr eng fre Canadian Science Publishing doi:10.1139/as-2017-0022 2368-7460 https://doaj.org/article/61315374aba64c36862e65bce241c866 undefined Arctic Science, Vol 4, Iss 1, Pp 25-41 (2018) hyperpycnal flows hypoxic high-conductivity bottom water permafrost degradation climate change polar limnology envir geo Journal Article https://vocabularies.coar-repositories.org/resource_types/c_6501/ 2018 fttriple https://doi.org/10.1139/as-2017-0022 2023-01-22T17:50:39Z In the deepest portions of many lakes, zones of high-conductivity bottom water (HCBW) depleted in dissolved oxygen (DO) are present. HCBW and DO are important for determining benthic diversity and abundance, nutrients, and contaminant cycling and understanding the long-term evolution of lakes. We investigate the persistence and removal of HCBW and DO replenishment in a High Arctic lake using physical properties and flow velocity data along with hydrometric and suspended sediment inflow data over a 4 year monitoring period (2007–2010). HCBW was removed in 2007 and 2008 but largely remained in 2009 and 2010. Catchment disturbances in 2007 increased suspended sediment concentrations (SSC) in the inflowing river in 2007 and 2008. In the later two years of monitoring (2009 and 2010), fluvial sediment availability relaxed to pre-disturbance levels. High SSC in 2007 and 2008 caused by landscape disturbances formed sustained river-generated hyperpycnal flows during the snowmelt period that are linked to HCBW removal. In 2009 and 2010, inflowing river water was periodically denser than lake water; however, HCBW was not removed in these years. Hyperpycnal flows were likely either of insufficient strength or duration, deposited on the delta front, or followed paths that led away from the deepest portion of the lake. Results suggest that hyperpycnal flow frequency will increase and HCBW persistence will decrease with projected climate change due to an increase in fluvial SSC inflow. Water density changes resulting from increased electrical conductivity and water temperature are not likely to have a similarly large effect on hyperpycnal flow frequency and HCBW. Article in Journal/Newspaper Arctic Arctic Climate change permafrost Unknown Arctic Arctic Lake ENVELOPE(-130.826,-130.826,57.231,57.231) Arctic Science |
institution |
Open Polar |
collection |
Unknown |
op_collection_id |
fttriple |
language |
English French |
topic |
hyperpycnal flows hypoxic high-conductivity bottom water permafrost degradation climate change polar limnology envir geo |
spellingShingle |
hyperpycnal flows hypoxic high-conductivity bottom water permafrost degradation climate change polar limnology envir geo Ted Lewis Scott F. Lamoureux Alexandre Normandeau Hilary A. Dugan Hyperpycnal flows control the persistence and flushing of hypoxic high-conductivity bottom water in a High Arctic lake |
topic_facet |
hyperpycnal flows hypoxic high-conductivity bottom water permafrost degradation climate change polar limnology envir geo |
description |
In the deepest portions of many lakes, zones of high-conductivity bottom water (HCBW) depleted in dissolved oxygen (DO) are present. HCBW and DO are important for determining benthic diversity and abundance, nutrients, and contaminant cycling and understanding the long-term evolution of lakes. We investigate the persistence and removal of HCBW and DO replenishment in a High Arctic lake using physical properties and flow velocity data along with hydrometric and suspended sediment inflow data over a 4 year monitoring period (2007–2010). HCBW was removed in 2007 and 2008 but largely remained in 2009 and 2010. Catchment disturbances in 2007 increased suspended sediment concentrations (SSC) in the inflowing river in 2007 and 2008. In the later two years of monitoring (2009 and 2010), fluvial sediment availability relaxed to pre-disturbance levels. High SSC in 2007 and 2008 caused by landscape disturbances formed sustained river-generated hyperpycnal flows during the snowmelt period that are linked to HCBW removal. In 2009 and 2010, inflowing river water was periodically denser than lake water; however, HCBW was not removed in these years. Hyperpycnal flows were likely either of insufficient strength or duration, deposited on the delta front, or followed paths that led away from the deepest portion of the lake. Results suggest that hyperpycnal flow frequency will increase and HCBW persistence will decrease with projected climate change due to an increase in fluvial SSC inflow. Water density changes resulting from increased electrical conductivity and water temperature are not likely to have a similarly large effect on hyperpycnal flow frequency and HCBW. |
format |
Article in Journal/Newspaper |
author |
Ted Lewis Scott F. Lamoureux Alexandre Normandeau Hilary A. Dugan |
author_facet |
Ted Lewis Scott F. Lamoureux Alexandre Normandeau Hilary A. Dugan |
author_sort |
Ted Lewis |
title |
Hyperpycnal flows control the persistence and flushing of hypoxic high-conductivity bottom water in a High Arctic lake |
title_short |
Hyperpycnal flows control the persistence and flushing of hypoxic high-conductivity bottom water in a High Arctic lake |
title_full |
Hyperpycnal flows control the persistence and flushing of hypoxic high-conductivity bottom water in a High Arctic lake |
title_fullStr |
Hyperpycnal flows control the persistence and flushing of hypoxic high-conductivity bottom water in a High Arctic lake |
title_full_unstemmed |
Hyperpycnal flows control the persistence and flushing of hypoxic high-conductivity bottom water in a High Arctic lake |
title_sort |
hyperpycnal flows control the persistence and flushing of hypoxic high-conductivity bottom water in a high arctic lake |
publisher |
Canadian Science Publishing |
publishDate |
2018 |
url |
https://doi.org/10.1139/as-2017-0022 https://doaj.org/article/61315374aba64c36862e65bce241c866 |
long_lat |
ENVELOPE(-130.826,-130.826,57.231,57.231) |
geographic |
Arctic Arctic Lake |
geographic_facet |
Arctic Arctic Lake |
genre |
Arctic Arctic Climate change permafrost |
genre_facet |
Arctic Arctic Climate change permafrost |
op_source |
Arctic Science, Vol 4, Iss 1, Pp 25-41 (2018) |
op_relation |
doi:10.1139/as-2017-0022 2368-7460 https://doaj.org/article/61315374aba64c36862e65bce241c866 |
op_rights |
undefined |
op_doi |
https://doi.org/10.1139/as-2017-0022 |
container_title |
Arctic Science |
_version_ |
1766294988859113472 |